Hi Sal...
Just catching up.
I was open minded as to who would be entered as Louisa's father and bear in mind Ellen could say whoever she liked. If I remember correctly I think the newspaper report re the bigamy trial said witnesses saw them in the street " last July" (July 1864) so they had been seen together.
In the beginning and when trying to verify if Joseph Dixon had married Ellen I was guessing the reference to Walley, Essex, could be Warley Camp and had also found the baptism.... but hadn't got any further.
I did a bit more digging because on one census Joseph says he and Ellen were cousins? but I didn't find anything to prove that.
The other observations were: that Joseph was a widower and on the 1841 census (Piece 651 / Book 2 / Folio 11 /Page 16 - St Botolph, Lincoln),and next door is a James Gregory aged 30 yrs and a Grinder, not born in the county (Lincs). Then there is a Mary Dixon aged 85... I thought she might be his mother, which made me wonder re the baptism at Great Warley.
The interesting one in the1841 household is the 15 year old boy, it looks like the name is written Maynes - but, I believe his name is Magnus Dixon.
So, I don't want to lead you up the garden path...... but I think it is interesting, I know you will relate to the coincidences.

There is this marriage for Magnus Dixon
Parish Bracebridge, Lincolnshire - 13th Nov 1848
Joseph Dixon & Margaret Neal
Grooms father = Joseph & Brides father = Daniel
I can't find an original parish entry on Lincstothepast etc
Updated to add.... found the marriage record -
http://www.rootschat.com/links/019vs/Disappointed to see it is an old style marriage register entry, the GRO version must have names of the fathers?

I can't find the couple in 1851 but they are here in 1861.
1861 - Piece 2338 /Folio 14 /Page 21 - Vauxhall, Skirbeck, Boston, Lincolnshire
Magnus Dixon Head, aged 34 - Grinder - born Nottingham, Nottinghamshire.
Margaret Dixon Wife - Married - aged 27 - born Derbyshire, England
George Dixon -Son - Scholar - born Scarborough, Yorkshire, England
Margaret Dixon, - aged 7 - Scholar - born Billinghay, Lincolnshire.
Joseph Dixon, Son - aged 3 - Scholar Beverley, Yorkshire, England
Catherine Dixon , Daughter - - 0 1861 - born Spalding, Lincolnshire, England
Baptism - NOTTINGHAM St Mary - 26th Dec 1826
Magnus Dixon - parents Joseph & Mary DIXON - occupation Chimney Sweeper - abode Bloomsbury Place
There are a couple of newspaper reports for Magnus & Margaret Dixon.
7 June 1861 - Stamford Mercury - Margaret Dixon, wife of Magnus Dixon, scissor-grinder of Skirbeck, convicted of assault.
21 Sept 1867 - Maidstone Telegraph - Magnus Dixon, Scissor Grinder - Robbery from the person - committed for trial at Borough Sessions.
9 Nov 1867 - Maidstone Telegraph - Magnus Dixon , aged 40, Umbrella Maker - acquitted.
I cannot see any of the above 1861 family on other census.
The only other census that I can find Magnus on is in 1881.
1881 - RG11 /Piece 960 /Folio 51/Page 11 - Lodging House, 9, Groves Lane, Canterbury,
Kent.Magnus Dixon, widower, aged 51, Hawker - born Nottingham.